This guidance document is one of a series produced with the support of the 2010 Biodiversity Indicators Partnership to assist Parties to the Convention on Biological Diversity to track their progress towards the 2010 Biodiversity Targets. The Wild Bird Index has been selected as one of the indicators suitable for assessing progress towards and communicating the 2010 target at the global level. The aim of this document is to provide guidance to support the calculation and interpretation of the Wild Bird Index at the national and regional scales.